Heat
by demonkatgurl17
Summary: Cora falls unexpectedly into heat. Peter coerces Derek into helping her.


"I can't _believe_ you're being so stubborn about this. Over a _technicality_," Peter scoffed, incredulous.

"A _technicality?_ Are you serious? She's my _younger __**sister**_, Peter. Where exactly is the technicality, here?" Derek spat in a furious whisper.

A thread moan filtered down from where the staircase met the upper floor of the loft, the same upper floor where Cora currently lay, bedridden and sweating and _writhing—_

Derek forced the thought of her like that away, of how she'd been for the past few hours now, struck by one of the…_conditions_…that fell upon the females of their kind from time to time. With so many alphas in one area, it was a miracle that Cora hadn't already fallen into heat sooner that she had, but with everything hurtling towards a head, Derek could only see it as yet another inconvenience from the universe. Then, again, she'd been held captive for three months by the alpha pack, it was possible that this wasn't her _first_ heat, and that thought made Derek clench his teeth around the protective rage that surged inside of him, imaging one or more of the males mounting his sister—

"Look, you're getting too hung up on the fact that she's your own flesh and blood," Peter said, stepping closer to Derek, his eyes almost shining with the force of his conviction as he tried (not for the first time since Cora lost the ability to walk, her coordination driven useless by the urge to mate). "What you really need to be focusing on is that she's a beta in need of a _knot_. That's something that I can't give her, otherwise we wouldn't be _having _this conversation," Peter finished, frustration biting into his tone.

"You'd fuck your own niece?" Derek asked, trying to ignore the way bile clawed at the back of his throat as _wrongwrongwrong_ went through his head.

"If I had what she needed, yes, because it's crueler to deny her this than to leave her to suffer through it out of whatever self-righteous morals that seem to be holding you back," Peter said, keeping his voice even with far more success that Derek was having. "She could be like this for _hours_, Derek. Days, even, if she's unlucky enough." It was rare, but it was possible. Derek remembered the horror stories from some of his older relatives. "Are you really going to punish her for sharing genes with you? For things that are beyond her control?"

Derek glanced away, his jaw clenched, hating the logic behind Peter's argument, whereas his own felt as ineffectual as a tattered rag, barely covering up the fact that he understood the points his uncle was making and yet was digging in his heels, desperately trying to think of a way around the issue (something that _didn't_ end with him fucking his own sister).

The sound of ragged breathing, loud in the open expanse of the loft despite the floor between them and Cora, was getting harder and harder to ignore, cloying its way into his brain and making it harder to think. Or it could just be the scent of her musk finally getting to him, growing stronger and stronger the longer she went without an alpha's knot.

"She'll be fine. She won't die from this. She just needs a chance to wait it out."

"_'Wait it out'?_" Peter's eyes widened, incredulous. "Do you hear her, Derek? She's in _agony_. You're condemning her to _agony_ just because you don't want to man up and be the alpha she needs."

A growl slipped from behind Derek's teeth at the dig, his eyes flashing red for a moment, but Peter just kept talking, ignoring the threat.

"What about her scent? It's only been a couple of hours, but you can smell it from outside the building already. The longer you put this off, the more chance there is of one of the alpha pack catching wind of it. And if they do, do you think they won't come in here and do what you won't? You've pissed them off quite a bit, I'm sure they'd just _love_ to add insult to injury by taking her in front of you."

The image sprang up of Cora, flat on her back as Ennis, or one of the twins, or _Deucalion _fucked his way inside his sister, of her bucking and writhing underneath one of them as she took their knot—

Derek snarled, his teeth elongating against the imagined threat and, from above them, came an answering snarl, the animal in Cora recognizing that there was an _alpha _nearby, uncaring that it was her own brother.

"She'd prefer it was you," Peter said, staring Derek down, his voice soft and almost kind, completely opposed to the fact that he was trying to what he was trying to persuade his nephew to do: taking his own sister when she couldn't even form the words to consent. "She would forgive you for it, for helping her like this. She's helpless right now, Derek. Don't leave her vulnerable to the alpha pack again. You and I both know we wouldn't be able to stop them be ourselves."

Derek knew. He hated it, but he knew exactly what would happen, what he'd have to listen—to _watch_—if they all came here. Internally, Derek felt his defiance sway, fury and shame warring within him as Kali's words echoed obscenely inside his head, only much differently: _family or pack?_

"You're her alpha now. _Be her alpha_." Peter coaxed, his eyes bright with suppressed emotion.

Seconds stretched between them, marred only by the helpless sounds Cora was making, while Peter's words tumbled through his mind over and over, making him cringe inside, but Derek had reached the point to where he couldn't think beyond his body's response to Cora's musk. The only clear thought in his head was that _no_ other alpha was getting anywhere _near _his sister, not while he could help it, but the scent of a werewolf in heat travels fast and far, a biological snare to any alpha within scenting distance to let them know that he was needed.

Derek needed to move before he wouldn't be able to salvage the situation.

Even if he'd hate himself for doing it.

Peter seemed to know the exact moment when the fight in Derek died because he gripped Derek's arm and slowly led his nephew towards the stairs, only having to tug on the taut appendage a few times to get Derek to follow him up and up and up…

The scent was almost overpowering in the upper room. Derek's knees tried to go out on him, momentarily weakened by both the musk of beta in heat and the last feeble twitches of his conscience trying to turn back, but then Peter was there, steadying him and drawing him forward towards the mattress Cora was laying on.

Isaac used to sleep on it, before Derek made him leave, but there was no trace of his scent here now, covered up by the heavy musk of Cora's heat.

She was naked, having clawed her clothes off in an effort to get cool, to get away from the need that had jacked her temperature sky high. The shredded remnants of her clothes were strewn about her sweat-slicked body.

Both the smell of Cora's heat and the result of six years apart made the last of Derek' protests die on his tongue.

This wasn't his baby sister. The sister he'd known had never had curves, or full, perky breasts. She'd never spread her legs wide at the sight of him, displaying her most private of places for all the world to see. She'd never smelled like need, like _sex_, never moaned in anything but frustration.

_This_ was a beautiful young beta, deep in the throes of the heat of their kind, and she needed to be filled.

She needed _him_.

Caught up in his staring, Derek was vaguely aware of Peter carefully slicing off his shirt, of having his belt and fly undone as his uncle eased down his jeans and boxers, the older man's hands sliding down his hips and thighs along with the clothes.

Peter knelt to untie the laces of Derek's shoes, helping him out of the last of his clothing, seemingly ignoring his nephew's erection bobbing in front of his face—at least until he pulled a condom from his pocket. "I think we'll avoid any…future…complications, if it's all the same to you," he muttered as he patiently rolled the latex over Derek's cock, pumping the length in his fist for a moment, making sure he condom was completely rolled down.

At least, that's what Derek preferred to think, anyway, as Peter touched him. He wasn't threated by his uncle's presence (as a Beta, Peter couldn't knot, and wouldn't be able to satisfy Cora if he tried), but the attention he was getting from the man wasn't unwelcome. Drunk on pheromones, all Derek wanted was to fuck and he really couldn't care who touched him.

His hips flexed of their own accord a few times in Peter's grip before his uncle stood and guided him the last few feet to the mattress, where Cora lay staring at him, her eyes slightly glazed with need.

It was easier than it should have been to kneel on the mattress, to crawl in between his sister's bent and spread legs, and run the length of his hard cock across her wet slit, sliding his shaft over it back and forth teasingly, eliciting a low growl from her. The sound sent a shiver down his spine and he bucked mindlessly, anticipation making him forget everything but the pleasure teasing him, circling him, urging him to take what was _his._

His balls were heavy and sensitive, and they drew up slightly when a hand closed around Derek's cock and angled the tip down, guiding it through the soft, wet folds and inin_in—_

Derek's instincts took over and he drove forward, sheathing himself completely in one quick thrust. Cora mewled beneath him, her hands winding around Derek's wrists as she pushed against the invading length, trying to get more inside. Withdrawing most of the way, Derek slammed back in, using more force than even a human could safely take as he began thrusting, his hips moving jack-rabbit fast, uncaring whether or not Cora had ever done this before.

He got lost in the wet slide of his sister's heat, in the moans and growls coming from her throat, that he didn't even notice Peter had stripped off his own clothing and climbed onto the mattress, too, until the older man was kneeling near Cora's thrown-back head, languidly fucking his own hand.

The smell of another male's precome mixed with Cora's heady scent and the combination made Derek just a little bit crazy. He reared back onto knees and pulled Cora onto his cock roughly with a tight, claw-tipped grip on her hips, snapping his pelvis against her as though to drive home the fact that she was _his_ to use, not Peter's.

Cora seemed to think otherwise, though.

Having caught Peter's scent, she angled her head towards him, her mouth open and wide, whining at him. She detached one of the hands she'd dug into the mattress when Derek had moved, reaching it out to Peter.

A feral smile curled at Peter's lips as he took her hand, inching forward on his knees until the dark pink tip of his cock was close enough that Cora could wrap her lips around it. He shuffled a bit closer so that he could start fucking her mouth, his eyes drifting half shut as he took his own pleasure, sliding in and out as if he had all the time in the world. Peter transferred her hand to his hip so that he could brace is hands on either side of Cora's head, holding her in place.

Jealousy curled into Derek's mind, making him thrust faster if only to remind Cora that he was there, that _he_ was the one fucking her, but the movements only served to impale her more on Peter's cock, muffling her groans and whimpers. He watched as Peter's hand stroked over the length of Cora's exposed throat, listened as his uncle crooned praises and sheer filth at her while she nursed at his thick cock.

Derek thrust in one last time and stilled, pushed over the edge by the utter depravity of the display. He let his knot swell inside Cora, forcing her walls to stretch around him, locking him in place while Peter continued to move.

Cora groaned around Peter's length, sucking him with enthusiasm while she rode out the shudder of Derek's orgasm. Her brother's come spilled into the condom, instead of her (as it was normally meant to) and she pawed at Peter's hips, needing to _feel_ the release of a male, to have it _stay_ inside her.

Using his thumbs to keep Cora's jaw open wide, Peter made fast and shallow thrusts into her mouth, then pushed in deep and stilled as well, his breath hitching as he spilled his come down his niece's throat.

His mind fuzzed from his own release, Derek watched the muscles in his sister's throat as it moved around Peter, swallowing the older man's release. Peter ran his fingers gently over Cora's throat, feeling it in two different ways, and he smiled down at her, satisfied, before he carefully withdrew from her mouth, his cock slick and spent.

Cora, on the other hand, was still writhing, trying to buck up onto Derek's cock despite the knot preventing him from moving in more than little twitches.

She hadn't come yet.

Under his uncle's approving gaze, Derek placed his thumb on her clit and massaged it, pressing down on it in firm, tight circles until she seized up around him, her body contracting in on herself in orgasm the same way her walls were fluttering around Derek's cock. Moaning faintly, he allowed himself to enjoy the feeling of her around him, watching with interest as Peter thumbed over her peaked nipples while she quaked and whimpered on the mattress.

Finally pulling away, Peter stretched out on the edge of the mattress, sighing contentedly.

It was a moment before Derek's knot shrank just enough for him to pull free, and when he did, Cora winced in pain as it left her, the emotion flitting across her face before it went blank again. Thoroughly exhausted, Derek eased himself from between his sister's legs and lay down too, settling on the other side of Cora, away from Peter. Distance wouldn't change anything, but he was determined to put off thinking about what he—what _they—_ had just done, until the last spikes of orgasm weren't rolling through him.

"I know at least one of you has to be freaking out right now," Cora drawled, her voice dry and cracking from dehydration and the throat-fucking, "but I'd kind of like to feel both of you in me again before we actually try to _talk_ about this."

Unbidden, a smile pulled at Derek's lips, and a similar one stretched across Peter's face, unseen by the other with Cora lying between them.

What else was family for?


End file.
